Nowadays a communication network comprises a variety of different devices and techniques. There are several generations of networks like 2G, 3G and 4G, which are under use in mobile communication networks. Each network technique requires specific devices so the mobile communication network or a fixed communication network has a great number of different devices and management systems.
Therefore, network operators have a great collection of different device types, including routers, firewalls, session border controllers, switches, aggregators, VPN gateways, and a variety of other device types. These devices are constantly being developed and acquired, so equipment rapidly becomes obsolete and should be replaced. The launch of new services often demands network reconfiguration and on-site installation of new equipment which in turn requires additional space and power. Further, the network can have unused capacity, which is not utilized efficiently partly due to a great variety of the network devices and techniques.
Further, network functions can be virtualized utilizing a network function virtualization (NFV) technique in order to be processed on normal servers, like x86 servers. The network function virtualization (NFV) makes it possible to replace traditional network devices with software that exists on servers. This software performs the network functions previously provided by dedicated hardware. The combination of a server and software can replace a wide range of network devices, from switches and routers to firewalls and VPN (virtual private network) gateways. These new solutions may run on physical servers, virtual machines controlled by hypervisors hosted by appropriate hardware (e.g. server) or a combination of them. As can be noted, it is very challenging to allocate resources of a modern communication network.
A service provider, like a network operator, may have unused physical capacity (processing power, routing capacity etc.), which the operator does not need himself, but wishes to utilize if possible. On the other hand, another service provider may need extra capacity, but does not wish to invest to new physical devices. There are known solutions in order that the service provider with extra capacity may offer capacity to another servicer provider who needs more capacity. An IP Multimedia Subsystem (IMS) is an architectural framework for delivering IP multimedia services, which is commonly used for this purpose. Although the known solutions as such works properly, they may be relatively slow. For example, a service provider may have need for extra capacity to a summer season only in a certain geographical area. Then a period of days or longer for achieving the extra capacity may be noticeable with respect to the season time.